Outdoor decks are extremely popular in residential home construction. Homes and apartments, as well as a variety of other buildings, often incorporate exterior decks into their design. Additionally, decks are commonly added onto existing structures and landscapes. These decks provide convenient spaces for a variety of outdoor activities, including cookouts, dining and sunbathing, as well as other leisure activities. Moreover, decks typically are provided with a railing or perimeter fence to keep people from falling over the edge of the deck.
Wood products traditionally have been the primary source of materials for use in decking construction. However, wood products are becoming increasingly scarce due to the harvesting of trees at ever faster rates and the rather limited rate at which timber resources can be replenished. Also, environmental concerns and regulations directed to conservation or preservation of forests tend to restrict the availability of wood products. With the diminishing availability of timber resources, wood products are becoming increasingly expensive. There is, therefore, a substantial need for long-lasting substitute construction materials that can lessen the need to harvest timber resources.
One potential approach to addressing the above need is to provide substitute decking products made of plastic, rather than wood. However, because the deck products must be capable of sustaining certain loads, the replacement products need to be stable and rigid. The material should also be capable of economical manufacture and be relatively inexpensive. It also needs to be easily installed and used in the field.
A variety of plastic building products are known. For example, U.S. Pat. No. 4,045,603 describes a three-layer synthetic construction material made from recycled waste thermoplastic synthetic resin material and cellulose fiber aggregate. This material includes face surfaces consisting essentially of re-hardened fused and rolled thermoplastic synthetic resin material bits, and an intervening core material consisting essentially of a compressed non-homogenous mixture of cellulose aggregate material bits and re-hardened fused thermoplastic synthetic resin material bits.
U.S. Pat. No. 3,764,245 describes an apparatus for producing a light structural board of thermoplastic resin.
U.S. Pat. No. 5,253,458 describes a simulated log made from a cast polyvinlychloride (PVC) pipe, selectively filled with a hard cast foam or bead type foam. This patent further describes that the cast PVC pipe is first manufactured and then subsequently filled with the foam filler.
U.S. Pat. No. 5,617,697 of Erwin (also the current Applicant) describes a composite deck post for use with a wood joist of wood deck which includes an elongate, hollow, extruded plastic shell in which an elongate tubular metal stiffening member is positioned there within and is rigidly secured thereto using a metal fastener that extends through the plastic shell and the stiffening member.
U.S. Pat. No. 5,626,331 of Erwin (also the current applicant) describes a composite spindle for use in a fence or deck railing and comprises a plastic outer shell having a first end section, a second end section opposite the first end section, and a middle section. An elongate metal reinforcing element is positioned within the outer shell and extends from the first end section to the second end section. A rigid plastic foam is placed within at least a portion of the first and second end sections and substantially surrounds portions of the metal reinforcing element.
Moreover, it is known in the art to construct railings out of plastic. For example, U.S. Pat. No. 4,477,058 of Lowery discloses a fence comprising plastic vertical posts, plastic horizontal rails interconnected to the posts by pins which pass through holes formed in the posts and in the ends of the horizontal rails, and plastic vertical fence boards having holes formed therein for receiving pegs extending from the horizontal rails for snapping the fence boards onto the horizontal rails.
U.S. Pat. No. 4,809,955 of Veilleux discloses a plastic fence or railing assembly comprising extruded plastic posts having U-shaped open-ended channels formed therein which function as guide slots for receiving the ends of horizontal rails inserted into the channels and held in a desired spatial relationship by separator elements.
U.S. Pat. No. 5,161,783 of German relates to a fence rail construction comprising hollow tubular PVC posts having openings formed therein for receiving a hollow tubular PVC rail. Prior to inserting the rail into the openings formed in the posts, a hollow tubular PVC sleeve having flanges is inserted within the posts in alignment with the openings formed in the posts. The ends of the rails are then inserted into the openings and the sleeves to form a rigid connection between the rails and the posts. In order to assemble the fence, openings are cut in the posts at the required heights. Adhesive is then applied to the sleeves which are then inserted into the hollow openings formed in the top of the posts, such that the sleeves are aligned with the openings formed in the posts. Adhesive is then applied to the ends of the horizontal rails which are then inserted into the openings formed in the posts and into the sleeves.
The plastic fencing or railing of the types just described represent an improvement over wood products in many respects, but generally suffer from being difficult or expensive to manufacture or assemble, requiring numerous small parts, and lack sufficient strength to be used as a deck railing (building codes are particularly strict with respect to the strength of plastic deck railings).
Accordingly, it can be seen that there is a need yet in the art for railing as a replacement for traditional wood railings, which provides a strong finished product at minimal cost, which is weather-resistant, and which can be produced and installed easily. It is to the provision of such a railing that the present invention is primarily directed.